//集合初始化
NSArray *array = [NSArray arrayWithObjects:@"aa", @"bb", @"cc", nil];
NSSet *se = [NSSet setWithArray:array];
NSLog(@"%@", se);
//集合里面只有一个元素
NSSet *set = [NSSet setWithObject:@"aa"]; //只能放一个
NSLog(@"%@", set);
NSSet *set1 = [NSSet setWithObjects:@"11",@"66",@"33",@"44",@"55",@"aa", nil]; //如果集合李有重复的会自动合并
NSLog(@"%@", set1);
//集合里面是否包含另一个集合Returns a Boolean value that indicates whether every object in the receiving set is also present in another given set.
//返回一个布尔值,表示接收组中的每一个对象是否还存在于另一个给定。
BOOL b = [set isSubsetOfSet:set1];
NSLog(@"/////******//////%d",b);
//返回一个任意元素,The object returned is chosen at the set’s convenience—the selection is not guaranteed to be random.
//返回的对象选择的设置convenience-the选择不能保证是随机的。
NSString *set2 = [set1 anyObject];
NSLog(@"%@", set2);
//返回所有的元素,存放在一个书组中,
NSArray *all = [set1 allObjects]; //调用所有的object
NSLog(@"0.0%@", all);
//计算集合长度,个数
NSLog(@"%ld", [set1 count]); //计算集合长度
//判断集合中是否包含某个对象
BOOL a = [set1 containsObject:@"11"]; //判断集合中是否包含某个对象
NSLog(@"%d", a);
//Returns an initialized mutable set with a given initial capacity.
NSMutableSet *muset = [NSMutableSet setWithCapacity:5];
//向里面存入元素
NSArray *arr = [NSArray arrayWithObjects:@"22", @"33",@"11", nil];
[muset addObjectsFromArray:arr];
NSLog(@"muset == %@", muset);
//移除元素
[muset removeObject:@"22"];
NSLog(@"%@", muset);
//可变集合
NSCountedSet *count = [NSCountedSet setWithObjects:@"22", @"33", @"33", @"66", nil];
NSInteger coun = [count countForObject:@"33"]; //计算集合中重复元素的个数
NSLog(@"%ld", coun);
//集合类型快速枚举
//书组中forin的快速遍历
NSArray *aaa = [NSArray arrayWithObjects:@"11", @"33", @"55", @"99", nil];
for (int i = 0; i < [aaa count]; i++) {
NSLog(@"aaa == %@", [aaa objectAtIndex:i]);
}
for (NSString *i in aaa) {
NSLog(@"forin == %@", i);
}
//字典中forin的快速遍历
NSArray *aaaa = [NSArray arrayWithObjects:@"11", @"22", @"33", @"44", nil];
NSArray *bbbb = [NSArray arrayWithObjects:@"aa", @"bb", @"cc", @"dd", nil];
NSMutableDictionary *cla = [NSMutableDictionary dictionaryWithObjects:bbbb forKeys:aaaa];
NSLog(@"%@", cla);
for (NSString *key in [cla allKeys]) { //forin前面的类型就是你要查询的 类型 ,,,切记 。
NSLog(@"value == %@", [cla objectForKey:key]);
}
集合
数学中有集合读概念
比如:整数集,自然数集
在比如:集合{1,2,5,}
集合特点
存储的元素互不相同
存储元素是无序的
存储元素必须是对象类型
容器有三个:NSArrey NSdictionary NSSet
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